Concerning elevator systems, a call-giving method is known wherein a passenger gives a so-called destination call in the elevator lobby before going into the elevator car. The elevator system registers the destination call given by the passenger and allocates immediately an elevator car to the passenger on the basis of the desired optimization criteria and also on the basis of the traffic situation prevailing in the elevator system. A destination call can generally be given by the aid of a call-giving panel disposed in the elevator lobby or by the aid of a personal terminal device. The elevator allocated is notified to the passenger who gave the call e.g. on the display of the call-giving device, after which the passenger can transfer to wait for the arrival of the elevator in question by the elevator. If the elevator system is congested, the arrival of the elevator can take many minutes. For example, in office buildings it is usual that employees arrive at roughly the same time at their workplace in the mornings, in which case so-called upward peak traffic forms in the elevator system. Correspondingly, in the afternoons, when most employees leave their workplace at roughly the same time, so-called downward peak traffic forms in the elevator system. Therefore, it is probable that passengers using the elevator system have to momentarily wait unreasonably long times for the elevators serving then, because the transport capacity of the elevator system is not sufficient to serve all the passengers for achieving the desired service targets. The central problem is that congestion occurs momentarily because passengers want to use the elevators at the same time of day.
So that the transport capacity of the elevator system could be utilized better, the transport capacity should be used more evenly and momentary traffic peaks should be avoided. In solutions according to prior art, this is generally not possible, if passengers are accustomed to using the elevators at the same times of day.